Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is getting confusing signals from two sensors that measure how fast parts inside the transmission are spinning. It's like when two friends tell you different times for the same event, and you don't know which one to trust.
The vehicle's computer monitors the input/turbine speed sensors to ensure they are providing consistent and accurate data. If the signals from these sensors do not match up as expected, the computer triggers the P2784 code.
The P2784 code is set when the Powertrain Control Module (PCM) detects a discrepancy between the readings from the input/turbine speed sensor A and sensor B. These sensors are responsible for monitoring the speed of the transmission input shaft, and their signals should correlate closely. A mismatch indicates a potential issue with one or both sensors or the transmission itself.
• Check Engine Light is on
• Transmission may shift improperly
• Reduced fuel efficiency
• Vehicle may enter 'limp mode'
• Faulty input/turbine speed sensor A or B
• Wiring issues such as shorts or open circuits
• Malfunctioning PCM
• Transmission mechanical issues
PCM: Powertrain Control Module, the vehicle's main computer for engine and transmission management.
Turbine Speed Sensor: A sensor that measures the rotational speed of the transmission's input shaft.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage
• Test the input/turbine speed sensors
• Check for any transmission mechanical issues
• Replace faulty input/turbine speed sensor
• Repair or replace damaged wiring or connectors
• Reprogram or replace the PCM if necessary
• Address any mechanical issues within the transmission
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain transmission components
• Ensure wiring and connectors are free from corrosion
• Perform routine diagnostic checks
Sensor Issue
• Do not ignore the Check Engine Light
• Have a professional diagnose the issue if unsure
• Avoid driving in harsh conditions until fixed
Check with your vehicle manufacturer, as some powertrain components may be covered under warranty.
The P2784 code has been associated with issues in vehicles with automatic transmissions, particularly as they age or if maintenance is neglected.
Moderate – Address the issue soon to prevent potential transmission damage.
Driving with transmission issues can be unsafe and may lead to further damage. It is advisable to have the vehicle inspected and repaired promptly.
• Vehicle at operating temperature
• Transmission in gear
The input/turbine speed sensors are typically located on or near the transmission housing.
Q: Can I drive with a P2784 code?
A: It's not recommended to drive for extended periods with this code, as it can lead to transmission damage.
Q: How do I reset the P2784 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, it should not return.
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